It is particularly simple in such oscillating grinders to design a tensioning device so that the abrasive paper can be inserted simply. In this connection it is for example known from German Offenlegungsschrift No. 25 11 392 to provide a clamping bar, which can be pivoted about an axis which extends parallel with respect to the upper side of the table plate and clamps with a free edge the abrasive paper against the upper side or the front surface of the table plate. Of course here too the threading of the abrasive paper and the operation of the tensioning device is complicated in comparison.
The purpose of the present invention is to further develop an abrasive paper connection for use on an oscillating grinder of the abovementioned type so that inserting the abrasive paper and operating the associated tensioning device is further simplified.
This purpose is attained inventively by the tensioning device including
(a) a clamping slide, which is movably guided parallel to the upper side or to the underside of the table plate and has an edge, which can rest at least partially on an end surface of the table plate;
(b) an eccentric mechanism, which can be operated by hand and thereby effects a movement of the clamping slide.
Thus inventively the abrasive paper is no longer clamped on the upper side but on the end surfaces of the table plate. The part which effects the clamping moves thereby linearly, whereby the course of movement is determined by an eccentric mechanism.
The clamping slide is preferably made of flat spring steel.
It can include:
(a) a flat main surface, which rests on a support surface on the table plate;
(b) a V-shaped bent section which follows the flat main surface; and
(c) an edge portion which follows the bent section and is bent back in direction of the front surface.
If at least two projecting teeth are provided on the edge portion, a still more reliable securing of the abrasive paper occurs, which paper has during tensioning the teeth extending therethrough. It is then favorable if bores are provided in the suitable end surface of the table plate, which bores receive the teeth in the closing position of the clamping slide.
At least two guide angle pieces can be arranged on both sides of the path of movement, which angle pieces laterally guide and grip over the clamping slide.
An eccentric mechanism is preferable which includes:
(a) a cylindrical guide surface on a locking handle which can be operated manually;
(b) a guide surface on the clamping slide, which guide surface is complementary with respect to the guide surface of the locking handle and which cooperates with the guide surface;
(c) an eccentric pin on the locking handle, the axis of which extends parallel and offset with respect to the axis of the guide surface on the locking handle;
(d) a slotted hole which is provided in the upper side of the table plate, which extends transversely with respect to the direction of movement of the clamping slide and in which the eccentric pin engages; and
(e) a device which linearly guides the clamping slide.
The guide surface of the locking handle can be the surface of a cylindrical shoulder, wherein the guide surface of the clamping slide is a circular hole, into which the shoulder is guided. Yet more advantageous is it if the guide surface of the locking handle is formed by several cylindrical surface segments, which are distributed at a desired angular spacing on the shoulder of the locking handle and project outwardly from the surface thereof; also in this case the guide surface of the clamping slide is formed by a circular hole. This construction assures that the locking handle can be rotated easily with respect to the clamping slide.
Concentrically below the cylindrical surface segments of the locking handle can follow radially projecting, downwardly tapered, elastically deformable teeth. The teeth are compressed during the installation of the locking handle through the associated circular hole in the clamping slide, which causes the locking handle to be axially fixed on the clamping slide.
All together it is preferable to manufacture the locking handle of plastic.